Fox's over-the-top convicts-vs.-cops drama Prison Break returns tonight (8 ET/PT) to a world where just about every authority figure is a bad guy:

•The federal agent (William Fichtner) chasing the escaped prisoners, led by Michael Scofield (Wentworth Miller), pops pills and has already shot one of the escapees in cold blood.

•The prison guard (Wade Williams) who was once in charge of the convicts was fired for being on the take and is now a bounty hunter also on their trail.

•A Secret Service agent (Paul Adelstein) also tracking the convicts is apparently an assassin under the implicit command of the president of the United States — who is not only corrupt herself, but may also have had a hand in the murder of the previous president and a state governor as part of some larger conspiracy.

Rebelling against authority has always been a popular concept of fiction. And suspicion of corruption at the highest levels is part of our history dating back to Richard Nixon, if not earlier. That distrust was echoed in last season's 24, where the president was at the root of a terrorist act.

"You're invoking the highest level of power in the country," says Olmstead. "That goes toward people's deep-rooted suspicion of politicians."

And when Prison Break (which is averaging 9.2 million viewers an episode so far for Season 2) returns tonight after its baseball-playoffs break, viewers will learn more about what drives FBI agent Alexander Mahone, played by Fichtner — who also played a sheriff gone bad in last year's sci-fi/government conspiracy drama Invasion.

Fichtner says, "Never once from the beginning, never once did I ever think Mahone was a bad guy. I've played some rough characters. But I think he's got a lot of demons driving him. In the month of November you are going to see that Mahone doesn't do everything he does because he wants to do it. He's not OK about it. It's going to start to come out."

One of the tricks writers use on Prison Break, Olmstead says, is to constantly shift the sympathetic characters. "A white-hat character can be kind of boring," he says.

This season also is exploring the motivations of Secret Service agent Paul Kellerman (Adelstein). He's wrestling with how far he'll go to do the dirty work, even in the name of freedom and democracy.

"My job is to figure out what makes this guy the most sincere, and that's that he believes in what he's doing," says Adelstein. "I think he's going to come up against some of that soon. He will start learning about aspects of what he's been serving that he didn't know about. That's when somebody like this could have a crisis of conscience."

Adelstein says the beauty of Prison Break is the underdog factor.

"Talk about insurmountable odds for your heroes: They're up against the biggest, baddest fighting machine in the world — the U.S. government," he says. "I guess since Watergate, people love a government conspiracy because it plays on their worst fears about what goes on. Even if it's pushed to a fantastical level, it makes for a great villain."

Adelstein says it's fun to think about whether the government really could be organized and devious enough to be behind an evil conspiracy of such magnitude. "You start to think: 'Are they actually capable of doing this? It'd be impressive.' "